Problem with SanDisk Extreme USB 2.0 Card Reader

Hi I’ve just bought the SanDisk Extreme USB 2.0 Card Reader. First i inserted my SD card into the reader. It reads. After i took it out and insert it back in, it doesn’t read. And it also doesn’t read other card too. All i have to do is safely remove the usb and plug it back into the computer, which is very annoying. I’ve tried ejecting the card from My Computer too. It eject just fine, but the same problem occur. Please help! I’ve try on both XP and Vista, same error!